翼型轴流桨推力系数实验及CFD模拟

对几种不同型式轴流桨的推力系数进行了实验及CFD模拟研究。结果表明:四宽叶翼型桨A的推力系数最大,三窄叶翼型桨D推力系数最小;模拟结果与实验结果有很好的吻合;四宽叶翼型桨A较其它几种轴流桨形成的全釜大循环更为彻底,没有发生分区现象;四宽叶翼型桨A在叶端线上的最大轴向速度远大于其它4种桨;四宽叶翼型桨A最大轴向速度随着r/R的增大而逐渐减小且逐渐向釜底方向移动。在水体系中的实验结果表明:当通气量Qg为1.1vvm,P/V≥1.5kW/m3时,四宽叶翼型桨A-透平桨组合的传质系数较双层透平桨组合高约9.6%。

Experimental study and CFD simulation for thrust coefficient of hydrofoil impellers

The thrust coefficient of different hydrofoil impellers was experimentally studied and simulated with CFD.Results showed that the thrust coefficient of four-broad-blade hydrofoil A is the largest,and that of three-narrow-blade hydrofoil D is the smallest.The simulation results axe in good agreement with experiment.Compared with other axial impellers,four-broad-blade hydrofoil A produces a fully developed circulation.The maximum axial velocity of four-broad-blade hydrofoil A is the biggest in these impellers at the vertical line of blade tip.The maximum axial velocity of four-broad-blade hydrofoil A gradually declines with the increase of r/R,and moves toward the bottom of the tank.Experimental results in water system indicated that the mass transfer coefficient (k_Lα) of four-broad-blade hydrofoil A-Rushton turbine (HF-A-RT) is 9.6% higher than that of Rushton turbine-Rushton turbine (RT-RT) when gas aerated rate is 1.1 vvm and the power consumption per volume (P/V) is not less than 1.5 kW/m~3.